1. Field of the Invention
This invention pertains to safety apparatus, and more particularly to safety apparatus for stopping a moving carriage of a mobile storage system upon command.
2. Description of the Prior Art
Mobile storage systems for storing books and similar items are in widespread use in libraries and offices. Mobile storage systems are popular because they conserve expensive floor space. Mobile storage systems with either manually or electrically powered movable carriages are commercially available.
An important part of a mobile storage system is the portion dealing with safely stopping a moving carriage in emergency situations. Such situations typically arise when a person is in an aisle adjacent a carriage and his presence is unknown to another person. The first person must be able to stop carriage movement that is started by the second person. One type of safety stop device is disclosed in U.S. Pat. No. 4,616,888. The disclosure of the U.S. Pat. No. 4,616,888 includes a mechanical brake in conjunction with a manually actuated safety sweep. Actuating the safety sweep activates a battery powered circuit to energize the brake and quickly and safely halt a moving carriage. Although quite satisfactory in operation, there are instances when it is desirable to employ 120 volt AC power for the safety circuit rather than battery power. For additional safety to persons using a mobile storage system, it is frequently desirable to place safety switches for energizing the carriage brake at locations other than the safety sweep. It is desirable for maintenance purposes that the safety circuit provide an indication of the location of the safety switch that was actuated to energize the safety brake.